Place the shredded lion’s mane and water into a saucepan and cook on medium heat with a lid on until the lion’s mane has shed most of its moisture (approximately 5 minutes). Cool the lion’s mane so that you can squeeze the remaining moisture out. Place in a mixing bowl.
Add the remaining ingredients to the bowl and mix together well. Place the mix in the fridge for at least 30 minutes to firm. Form the mixture into generous patties and coat with the remaining breadcrumbs. Heat a good glug of vegetable oil in a frying pan to medium and add the patties. Cook completely on one side before trying to turn the patties over. They will be delicate!
Serve on burger buns with crispy lettuce, grated carrot and chipotle mayonnaise.